The subject matter disclosed herein relates generally to the field of structural health monitoring and, more particularly, to structural masking for progressive health monitoring of a structural component.
Visual inspection has been used in the aerospace industry for detecting aircraft surface and sub-surface defects. Typical defects in aircraft structures include cracks, corrosion, and disbonding. Visual inspection (such as by a person) has been widely used for detecting cracks in aircraft structures as it is often an economical and quick method to gauge a condition of the aircraft structure (notwithstanding the questionable reliability of human inspection). Cracks typically appear in areas that experience fatigue such as, for example, at holes for rivets, bolts, etc. These areas, commonly referred to as “hot spots” may be located in certain inaccessible areas of the aircraft, for example hidden behind other structures or panels, and may not be amenable to visual inspection. These hot spots may be manually inspected by remote imaging methods, e.g., utilizing a borescope, and include preferential inspection of analytically predicted hot spot locations. However, these manual image-based methods can be cumbersome and are used in limited circumstances.